Note: Descriptions are shown in the official language in which they were submitted.
CA 02382594 2002-04-18
PRESSURIZED VALVE SEAL
Field of Invention
This invention relates to valve seals, and particularly pressurized valve
seals.
Background of the Invention
Valves typically employ a resilient seating material, such as an o-ring, about
the
perimeter of a port or aperture. The resilient seating material is intended to
engage and be
compressed by a movable valve sealing member to effect sealing of the port or
aperture.
The seating material is disposed and contained within a sealing gland,
provided in the
body of the valve. In order to achieve desirable sealing properties, the
seating material
must be sealingly engaged to the sealing gland both upstream and downstream of
the
point of sealing engagement between the valve sealing member and the seating
material.
Under some operating conditions, the seating member moves away from the
sealing
gland, creating a flow path, allowing fluid to leak through the port or
aperture even
though the valve sealing member is sealingly engaged to the seating material.
Under
these circumstances, sealing engagement of the valve sealing member to the
seating
material is ineffective in sealing the port or aperture.
To mitigate this problem, it is known to pressurize the cavity within the
sealing
gland, to thereby provide fluid pressure forces to act upon the seating
material, opposing
those fluid pressure forces acting on the seating material from within the
fluid passage,
and thereby mitigating loss of sealing engagement between the seating material
and the
sealing gland. An example of such a pressurized seal is disclosed in U.S.
Patent No.
5,474,104.
Valves with pressurized seals continue to experience problems with maintaining
sealing engagement of the seating surface against the sealing gland. Because
the seating
CA 02382594 2002-04-18
surface is pressed into the cavity of the sealing gland, the seating surface
is sealingly
engaged to the sealing gland at multiple points, thereby creating multiple
individual
cavities between the seating surface and the sealing gland. It is believed
that fluid
introduced into the sealing gland, for purposes of pressurizing the seal, does
not access
these individual cavities. As a result, fluid pressure introduced into the
sealing gland
cavity is not necessarily effective in opposing the fluid pressure forces
acting on the
seating member from within the fluid passage, thereby potentially compromising
the
sealing of the seating member to the sealing gland.
Summary of the Invention
In one aspect, the present invention provides a valve comprising a body
including a fluid passage, a valve seat including a sealing gland including a
support
surface, the support surface including a notch, and a resilient valve seat
member sealingly
disposed within the sealing gland, and a valve sealing member disposed within
the fluid
passage and configured to sealingly engage the valve seat member to effect
sealing of the
valve sealing member to the valve seat, wherein the notch is configured to
facilitate
application of a fluid pressure on the resilient valve seat member to maintain
sealing
engagement between the valve seat member and the sealing gland.
In another aspect, the present invention provides a valve comprising a
body including a fluid passage, a valve seat defining an orifice, and
including a sealing
gland, and a resilient valve seat member disposed within the sealing gland,
and including
a notch, and a valve sealing member disposed within the fluid passage and
configured to
seat against the valve seat member to effect sealing of the valve sealing
member to the
valve seat and thereby close the orifice, wherein the notch is configured to
facilitate
application of the fluid pressure on the valve seat member to prevent leakage
through the
orifice when the valve sealing member is seated against the valve seat member.
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In a further aspect, the present invention provides any of the valves
described above wherein the notch is configured to facilitate the application
of the second
fluid pressure on the valve seat member to prevent leakage through the orifice
and
between the valve sealing member and the sealing gland when the valve sealing
member
is seated against the valve seat member.
In a further aspect, the present invention provides any of the valves
described above wherein the valve seat member includes a first pressure
responsive
surface, exposed to the fluid passage, and including a valve engaging surface
portion,
wherein the valve engaging surface portion is configured to engage the valve
sealing
member to effect sealing of the valve sealing member to the valve seat, a
second pressure
responsive surface configured to receive the application of the fluid
pressure, wherein the
notch is configured to facilitate the application of the fluid pressure on the
second
pressure responsive surface to maintain engagement of the valve seat member to
the
sealing gland upstream of the valve engaging surface.
In a further aspect, the present invention provides any of the valves
described above wherein the notch is configured to facilitate application of
the fluid
pressure on the second pressure responsive surface to counterbalance an
application of
forces on the first pressure responsive surface.
In a further aspect, the present invention provides any of the valves
described above, wherein the second pressure responsive surface opposes the
notch.
In a further aspect, the present invention provides any of the valves
described above, wherein the valve seat member is supported within the sealing
gland.
In a further aspect, the present invention provides any of the valves
described above, wherein the sealing gland includes a cavity in communication
with the
CA 02382594 2002-04-18
fluid pressure source, wherein the cavity includes a channel between the
support surface
and the second pressure responsive member defined by the notch.
In a further aspect, the present invention provides any of the valves
described above, wherein the notch is characterized by a depth of at least 100
microinches, or at least 0.001 inches.
In a further aspect, the present invention provides any of the valves
described above, wherein the first pressure responsive surface is opposite to
the second
pressure responsive surface.
In a further aspect, the present invention provides any of the valves
described above, wherein the fluid passage is the fluid pressure source.
In a further aspect, the present invention provides any of the valves
described above, wherein the valve further includes a pressure communication
passage
effecting communication between the cavity of the sealing gland and the fluid
passage.
In a further aspect, the present invention provides any of the valves
described above, wherein the sealing gland includes an aperture, and wherein
the pressure
communication passage is coupled to the aperture.
In a further aspect, the present invention provides a valve comprising a
body including a fluid passage, a valve seat, defining an orifice, and
including a sealing
gland including a cavity, and a resilient valve seat member disposed within
the sealing
gland, and a valve sealing member disposed within the fluid passage and
configured to
seat against the valve seat member to effect sealing of the valve sealing
member to the
valve seat and thereby close the orifice, wherein the sealing gland includes
at least two
spaced-apart apertures, and wherein the spaced-apart apertures are configured
to
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distribute fluid pressure within the cavity to act upon the valve seat member
to prevent
leakage through the orifice when the valve sealing member is seated against
the valve seat
member.
In a further aspect, the present invention provides a pressurized valve seat
defining an orifice and configured for use in a valve comprising a fluid
passage and a
valve sealing member disposed within the fluid passage, wherein the valve seat
comprises
a sealing gland including a support surface, the support surface including a
notch, and a
resilient valve seat member disposed within the sealing gland, and configured
to engage
the valve sealing member to effect sealing of the valve sealing member to the
valve seat
and thereby closing the orifice, wherein the notch is configured to facilitate
application of
a fluid pressure on the valve seat member to prevent leakage through the
orifice when the
valve sealing member is engaged to the valve seat member.
1n a further aspect, the present invention provides a pressurized valve seat
defining an orifice and configured for use in a valve comprising a fluid
passage and a
valve sealing member disposed within the fluid passage, wherein the valve seat
comprises
a sealing gland, and a resilient valve seat member disposed within the sealing
gland, and
configured to engage the valve sealing member to effect sealing of the valve
sealing
member to the valve seat and thereby closing the orifice, and including a
notch, wherein
the notch is configured to facilitate application of a fluid pressure on the
valve seat
member to prevent leakage through the orifice when the valve sealing member is
engaged
to the valve seat member.
In a further aspect, the present invention provides a pressurized valve seat
defining an orifice and configured for use in a valve comprising a fluid
passage and a
valve sealing member disposed within the fluid passage, wherein the valve seat
comprises
a sealing gland including a cavity, and a resilient valve seat member disposed
within the
sealing gland and configured to engage the valve sealing member to effect
sealing of the
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valve sealing member to the valve seat and thereby closing the orifice,
wherein the
sealing gland includes at least two spaced apart apertures, and wherein the
spaced apart
apertures are configured to distribute fluid pressure within the cavity to act
upon the valve
seat member to prevent leakage through the orifice when the valve sealing
member is
S engaged to the valve seat member.
Brief Description of Drawings
The embodiments of the present invention are described below with reference to
the
accompanying drawings in which:
Figure 1 is a sectional elevation view of an embodiment of the valve of the
present invention;
Figure 2 is a detailed sectional elevation view, partly cut-away, of the
valve seat area of the valve illustrated in Figure 1;
Figure 3 is a plan view of the valve illustrated in Figures 1 and 2, taken
along the lines 3-3 in Figure 2;
Figure 4 is a sectional elevation view of another embodiment of the valve
of the present invention;
Figure S is a detailed sectional elevation view, partly cut-away, of the
valve seat area of the valve in Figure 4;
Figure 6 is a plan view of the valve illustrated in Figures 4 and 5, taken
along the lines 6-6 in Figure S;
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Figure 7 is a sectional elevation view of another embodiment of the valve
of the present invention;
Figure 8 is a sectional elevation view, partly cut-away, of the valve seat
S area of the valve illustrated in Figure 7.
Detailed Description
Refernng to Figures 1 and 2, in one embodiment, the present invention
provides a valve 10 comprising a body 12 including a fluid passage 14, a valve
seat 16,
and a communication channel 18. The valve seat 16 includes a sealing gland 20
and a
resilient valve seat member 22 disposed and supported within a cavity 24 of
the sealing
gland 20. The sealing gland 20 has a support surface 26 including a notch 28.
The notch
28 defines a channel which forms part of the cavity 24. The communication
channel 18
effects communication between the fluid passage 14 and the cavity 24, and,
therefore, the
notch 28, through an aperture 30 provided in the sealing gland 20. In this
respect, the
communication channel 18 provides a means for effecting communication between
the
cavity 24 and a source of fluid pressure (in this case, the fluid passage).
The body 12 is made of a material which is significantly harder than the
material of construction of the valve seat member 22. The valve seat member 22
is made
of a resilient material, such as an elastomeric rubber, for example, nitrite
rubber. In turn,
the body is made of steel, such as stainless steel, brass, or a hard polymer.
A valve sealing member 32 is disposed within the passage 14. The valve
sealing member 32 is configured to seal against the valve seat 16. In this
respect, the
valve sealing member 32 is configured to seat against the valve seat member 22
which is
disposed within the sealing gland 20 of the valve seat 16.
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CA 02382594 2002-04-18
The valve sealing member 32 can be of the form which is biassed to close
an orifice 35 defined by the valve seat 16. In this respect, the valve sealing
member 32
can be urged into engagement with the valve seat member 22 by a resilient
member 33,
such as a compression spring. The valve sealing member 32 is unseated by fluid
pressure
upstream of the valve sealing member 32 (ie. in a direction opposite from the
direction in
which the force imparted by the resilient member acts upon the valve sealing
member
32). It is understood that the present invention is not limited to such spring-
loaded, one
way valves. For example, the present invention may be incorporated in solenoid-
actuated
valves and pintle valves.
The valve seat member 22 includes a first pressure responsive surface 34
and a second pressure responsive surface 36. The first pressure responsive
surface 34 is
exposed to the fluid passage. The second pressure responsive surface 36 is
configured to
receive application of a fluid pressure from within the cavity 24, and is
opposite the first
pressure responsive surface 34.
The first pressure responsive surface 34 is configured to engage the valve
sealing member 32 to effect sealing of the valve sealing member 32 to the
valve seat 16.
The first pressure responsive surface 34 receives application of forces from
the valve
sealing member 32 (when the valve sealing member 32 engages the first pressure
responsive surface 34) and the fluid pressure forces in the fluid passage 14.
The first
pressure responsive surface 34 includes a valve engaging surface 38,
configured to
engage the valve sealing member 32.
Sealing of the valve sealing member 32 to the valve seat 16 requires that
the valve seat member 22 bridge the gap across the sealing gland 20 upstream
40 of the
valve engaging surface 38. In this respect, the valve seat member 22 is
maintained
engaged to the sealing gland 20 upstream 40 of the valve engaging surface 38
of the first
pressure responsive surface 34.
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CA 02382594 2002-04-18
The valve seat member can be in the form of an o-ring or any other
compliant seal of various cross-sectional shapes.
To maintain the necessary engagement between the valve seat member 22
and the sealing gland 20, a fluid pressure is introduced into the cavity 24 of
the sealing
gland 20 to act upon the second pressure responsive surface 36. In this
respect, this fluid
pressure opposes or counterbalances the above-described forces acting on the
first
pressure responsive surface 34 such that the valve seat member 22 remains
engaged to the
sealing gland 20.
As perhaps best illustrated in Figure 2, the notch 28 is deliberately formed
in the support surface 26 of the sealing gland 20, and functions as a channel
to effect
distribution of fluid pressure through the cavity 24, the fluid pressure being
introduced
into the cavity 24 through the aperture 30 in the sealing gland 20. In this
respect, the
notch 28 and the valve seat member 24 are co-operatively configured so that
the valve
seat member 22 is not capable, upon deformation, of sealing the channel
defined by the
notch 28. The notch 28 is provided to mitigate against the risk that the valve
seat member
22 engages the sealing gland 20 and impedes distribution of fluid pressure
through the
cavity 24. By impeding distribution in this manner, the effectiveness of the
introduced
fluid pressure in opposing or counterbalancing the above-described forces
being applied
to the first pressure responsive surface 34 would be compromised.
In this respect, the notch 28 opposes the second pressure responsive
surface 36 of the valve seat member 22, and is configured to facilitate
application of a
fluid pressure on the valve seat member 22, and specifically the second
pressure
responsive surface 36 of the valve seat member 22 to prevent leakage through
the orifice
when the valve sealing member 32 is seated against the valve seat member 22.
Similarly, the notch 28 is also configured to facilitate the application of
the fluid pressure
on the valve seat member 22 to prevent leakage through the orifice 35 and
between the
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CA 02382594 2002-04-18
valve sealing member 32 and the sealing gland 20 when the valve sealing member
32 is
seated against the valve seat member 22. The notch 28 is also configured to
facilitate
application of the fluid pressure on the second pressure responsive surface 36
to
counterbalance the application of the above-described forces on the first
pressure
responsive surface 34 of the valve seat member 22.
In one embodiment, the notch 28 is characterized by a depth of at least 100
micro-inches. In another embodiment, the depth of the notch is at least 0.001
inches.
Preferably, the notch 28 is characterized by a depth of from 0.020 inches to
0.030 inches.
Referring to Figures 3 and 4, in another embodiment, the present invention
provides a valve 110 comprising a body 112 including a fluid passage 114, a
valve seat
116, and a communication channel 118. The valve seat 116 includes a sealing
gland 120
and a resilient valve seat member 122 disposed and supported within a cavity
124 of the
sealing gland 120. The resilient valve seat member 122 includes a notch 128
opposing a
support surface 126 of the sealing gland 120. The notch 128 defines a channel
which
forms part of the cavity 124 of the sealing gland 120. The communication
channel 118
effects communication between the fluid passage 114 and the cavity 124, and,
therefore,
the notch 128, through an aperture 130 provided in the sealing gland 120. In
this respect,
the communication channel l 18 provides a means for effecting communication
between
the cavity 124 and a source of fluid pressure (in this case, the fluid passage
114).
The body 112 is made of a material which is significantly harder than the
material of construction of the valve seat member 122. The valve seat member
122 is
made of a resilient material, such as an elastomeric rubber, for example,
nitrile rubber. In
turn, the body is made of steel, such as stainless steel, brass, or a hard
polymer.
A valve sealing member 132 is disposed within the passage 114 . The
valve sealing member 132 is configured to seal against the valve seat 116. In
this respect,
CA 02382594 2002-04-18
the valve sealing member 132 is configured to seat against or engage the valve
seat
member 122 which is disposed within the sealing gland 120 of the valve seat
116.
The valve sealing member 132 can be of the form which is biased to close
an orifice 135 defined by the valve seat 16. In this respect, the valve
sealing member 132
can be urged into engagement with the valve seat member 122 by a resilient
member 133,
such as a compression spring. The valve sealing member 132 is unseated by
fluid
pressure upstream of the valve sealing member 132 (i.e. in a direction
opposite from the
direction in which the force imparted by the resilient member acts upon the
valve sealing
member 132). It is understood that the present invention is not limited to
such spring-
loaded, one way valves. For example, the present invention may be incorporated
in
solenoid-actuated valves and pintle valves.
The valve seat member 122 includes a first pressure responsive surface
134 and a second pressure responsive surface 136. The first pressure
responsive surface
134 is exposed to the fluid passage 114. The second pressure responsive
surface 136 is
configured to receive application of a fluid pressure, and is opposite the
first pressure
responsive surface 134.
The first pressure responsive surface 134 is configured to engage the valve
sealing member 132 to effect sealing of the valve sealing member 132 to the
valve seat
116. The first pressure responsive surface receives 134 application of forces
from the
valve sealing member 132 (when the valve sealing member 132 engages the first
pressure
responsive surface 134) and the fluid pressure forces in the first fluid
passage114 . The
first pressure responsive surface 134 includes a valve engaging surface 138,
configured to
engage the valve sealing member 132.
Sealing of the valve sealing member 132 to the valve seat 116 requires that
the valve seat member 122 bridge the gap across the sealing gland 120 upstream
140 of
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CA 02382594 2002-04-18
the valve engaging surface 138. In this respect, the valve seat member 122 is
maintained
engaged to the sealing gland 120 upstream 140 of the valve engaging surface
138 of the
first pressure responsive surface 134.
The valve seat member 122 can be in the form of an o-ring or any other
compliant seal of various cross-sectional shapes.
To maintain the necessary engagement between the valve seat member 122
and the sealing gland 120 , a fluid pressure is introduced into the cavity 124
of the sealing
gland 120 to act upon the second pressure responsive surface 136. In this
respect, this
fluid pressure opposes or counterbalances the above-described forces acting on
the first
pressure responsive surface 134 such that the valve seat member remains
engaged to the
sealing gland 120.
As perhaps best shown in Figure 4, the notch 128 is deliberately formed in
the second pressure responsive surface 136 of the valve seat member 122, and
functions
as a channel to effect distribution of fluid pressure throughout the cavity
124, the fluid
pressure being introduced into the cavity 124 through the aperture 130 in the
sealing
gland 120. The notch 128 is configured so that the valve seat member 122 is
not capable,
upon deformation, of collapsing the notch 128. The notch 128 is provided to
mitigate
against the risk that the valve seat member 122 engages the sealing gland 120
and
impedes distribution of fluid pressure throughout the cavity 124. By impeding
distribution in this manner, the effectiveness of the introduced fluid
pressure in opposing
or counterbalancing the above-described forces being applied to the first
pressure
responsive surface 134 would be compromised.
In this respect, the notch 128 opposes the support surface 126 of the
sealing gland 120, and is configured to facilitate application of a fluid
pressure on the
valve seat member 122, and specifically the second pressure responsive surface
136 of the
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CA 02382594 2002-04-18
valve seat member 122, to prevent leakage through the orifice 135 when the
valve
sealing member 132 is seated against the valve seat member 122. Similarly, the
notch
128 is also configured to facilitate the application of the fluid pressure on
the valve seat
member 122 to prevent leakage through the orifice 135 and between the valve
sealing
member 132 and the sealing gland 120 when the valve sealing member 132 is
seated
against the valve seat member 122. The notch 128 is also configured to
facilitate
application of the fluid pressure on the second pressure responsive surface
136 to
counterbalance the application of the above-described forces on the first
pressure
responsive surface 134 of the valve seat member 122.
In one embodiment, the notch 128 is characterized by a depth of at least
100 microinches. In another embodiment, the depth of notch 128 is at least
0.001 inches.
Preferably, the notch 128 is characterized by a depth of between 0.020 inches
and 0.030
inches.
Refernng to Figure 5, in another embodiment, the present invention
provides a valve 210 comprising a body 212 including a fluid passage 214, a
valve seat
216, and first and second communication channels 218a, 218b. The valve seat
includes a
sealing gland 220 and a resilient valve seat member 222 disposed and supported
within a
cavity 224 of the sealing gland 220. The sealing gland 220 includes first and
second
spaced apart apertures 230a, 230b communicating with the first and second
communication channels 218a, 218b, respectively. The communication channels
218a,
218b effects communication between the fluid passage 214 and the cavity 224,
thereby
providing a means for effecting communication between the cavity 224 and a
source of
fluid pressure (in this case, the fluid passage 214).
The body 212 is made of a material which is significantly harder than the
material of construction of the valve seat member 222. The valve seat member
222 is
made of a resilient material, such as an elastomeric rubber, for example,
nitrite rubber. In
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CA 02382594 2002-04-18
turn, the body is made of steel, such as stainless steel, brass, or a hard
polymer.
A valve sealing member 232 is disposed within the passage 214. The
sealing member 232 is configured to seal against the valve seat 216. In this
respect, the
valve sealing member 232 is configured to seat against or engage the valve
seat member
222 which is disposed within the sealing gland 220.
The valve seat member 222 includes a first pressure responsive surface
234 and a second pressure responsive surface 236. The first pressure
responsive surface
234 is exposed to the fluid passage 214. The second pressure responsive
surface 236 is
configured to receive application of a fluid pressure from within the cavity
224, and is
opposite the first pressure responsive surface 234.
The first pressure responsive surface 234 is configured to engage the valve
sealing member 232 to effect sealing of the valve sealing member 232 to the
valve seat
216. The first pressure responsive surface 232 receives application of forces
from the
valve sealing member 232 (when the valve sealing member 232 engages the first
pressure
responsive surface 234) and the fluid pressure forces in the fluid passage
214. The first
pressure responsive surface 234 includes a valve engaging surface 238,
configured to
engage the valve sealing member 232.
Sealing of the valve sealing member 232 to the valve seat 216 requires that
the valve seat member 222 bridge the gap across the sealing gland 220 upstream
240 of
the valve engaging surface 238. In this respect, the valve seat member 222 is
maintained
engaged to the sealing gland 220 upstream 240 of the valve engaging surface
238 of the
first pressure responsive surface 234.
The valve seat member can be in the form of an o-ring or any other
compliant seal of various cross-sectional shapes.
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CA 02382594 2002-04-18
To maintain the necessary engagement between the valve seat member 222
and the sealing gland 220, a fluid pressure is introduced into the cavity 224
of the sealing
gland to act upon the second pressure responsive surface 236. In this respect,
this fluid
pressure opposes or counterbalances the above-described forces acting on the
first
pressure responsive surface such that the valve seat member 222 remains
engaged to the
sealing gland 220.
The first and second spaced apart apertures 230a, 230b are formed in the
sealing gland 220 and are each configured to act as a means for introducing
fluid pressure
into the cavity 224. In this respect, the first and second apertures 230a,
230b function as
first and second means for introducing fluid pressure into the sealing gland
cavity 224.
Introducing fluid pressure into the cavity 224 at different points within the
sealing gland
220 functions as a means for effecting distribution of fluid pressure through
the cavity
224. The multiple points of introduction are provided to mitigate against the
risk that the
valve seat member 222 engages the sealing gland 220 to form multiple isolated
cavities
and thereby impeding distribution of fluid pressure through the cavity 224. By
impeding
distribution in this manner, the effectiveness of the introduced fluid
pressure in opposing
or counterbalancing the above-described forces being applied to the first
pressure
responsive surface 234 would be compromised.
In this respect, the first and second means for introducing fluid pressure
into the sealing gland cavity 220 are configured to facilitate application of
a fluid pressure
on the valve seat member 222, and specifically the second pressure responsive
surface
236 of the valve seat member 222, to prevent leakage through the orifice when
the valve
sealing member 232 is seated against the valve seat member 222. Similarly, the
first and
second means are also configured to facilitate the application of the
distributed fluid
pressure on the valve seat member 222 to prevent leakage through the orifice
235 and
between the valve sealing member 232 and the sealing gland 220 when the valve
sealing
member 232 is seated against the valve seat member 232. The first and second
means
CA 02382594 2002-04-18
are also configured to facilitate application of the fluid pressure on the
second pressure
responsive surface 236 to counterbalance the application of the above-
described forces on
the first pressure responsive surface 234 of the valve seat member 222. It is
understood
that the invention is not limited to the provision of only first and second
means for
introducing fluid pressure into the sealing gland cavity, and further such
means may be
provided to effect distribution of fluid pressure within the sealing gland
cavity 224 with a
view to opposing forces applied to the first pressure responsive surface 234
and
maintaining the necessary engagement between the valve seat member 222 and the
sealing gland 220
Although the disclosure describes and illustrates preferred embodiments of
the invention, it is to be understood that the invention is not limited to
these particular
embodiments. Many variations and modifications will now occur to those skilled
in the
art. For definition of the invention, reference is to be made to the appended
claims..
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